Testing Amplifier Output

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  • bwilliams60
    Senior Member
    • Aug 2014
    • 109
    • Canada

    #1

    Testing Amplifier Output

    I was wondering if someone could explain to me how you go about putting a signal into an amplifier and checking it on the output side with an oscilloscope. I have an amp with a fuzzy channel and I have read that you can input a signal to the amp, and then compare the two channels output for differences. How is this done? I am obviously a newb but I want to learn anything I can about amplifier repair, TV repair, whatever.
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 31003
    • Albion

    #2
    Re: Testing Amplifier Output

    you need to generate a signal the amp will handle, so 50hz > 15khz is o.k.
    most scopes have a squarewave output for calibrating the probes - maybe that can be used.

    Comment

    • diif
      Badcaps Legend
      • Feb 2014
      • 6978
      • England

      #3
      Re: Testing Amplifier Output

      I'm guessing something like this could be used ?
      http://www.ebay.co.uk/itm/New-DDS-Fu...item417a5aadb2

      Comment

      • stj
        Great Sage 齊天大聖
        • Dec 2009
        • 31003
        • Albion

        #4
        Re: Testing Amplifier Output

        damn that's nice.
        do you know 10years ago something like that would set you back hundreds!

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA

          #5
          Re: Testing Amplifier Output

          You can use your PC for tone generator, it's free:
          http://onlinetonegenerator.com/
          Never stop learning
          Basic LCD TV and Monitor troubleshooting guides.
          http://www.badcaps.net/forum/showthr...956#post305956

          Voltage Regulator (LDO) testing:
          http://www.badcaps.net/forum/showthr...999#post300999

          Inverter testing using old CFL:
          http://www.badcaps.net/forum/showthr...er+testing+cfl

          Tear down pictures : Hit the ">" Show Albums and stories" on the left side
          http://s807.photobucket.com/user/budm/library/

          TV Factory reset codes listing:
          http://www.badcaps.net/forum/showthread.php?t=24809

          Comment

          • bwilliams60
            Senior Member
            • Aug 2014
            • 109
            • Canada

            #6
            Re: Testing Amplifier Output

            Okay, I have a WAVETEK sweep generator Model 22 that I had given to me and a Phillips PM3217 Oscilloscope. Both units are a little older but still work. What I want to know is how to hook it up, and where to set it and what I am actually looking for once it is working? Is the amp plugged in or am I doing this on a cold circuit.
            I also have a PICOSCOPE PC based oscilloscope that I can use as well. Patience please, I will get this. Like a sponge

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #7
              Re: Testing Amplifier Output

              Make and model of the amplifier you are working on? Upload pictures of the amp also.
              Never stop learning
              Basic LCD TV and Monitor troubleshooting guides.
              http://www.badcaps.net/forum/showthr...956#post305956

              Voltage Regulator (LDO) testing:
              http://www.badcaps.net/forum/showthr...999#post300999

              Inverter testing using old CFL:
              http://www.badcaps.net/forum/showthr...er+testing+cfl

              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
              http://s807.photobucket.com/user/budm/library/

              TV Factory reset codes listing:
              http://www.badcaps.net/forum/showthread.php?t=24809

              Comment

              • bwilliams60
                Senior Member
                • Aug 2014
                • 109
                • Canada

                #8
                Re: Testing Amplifier Output

                It is a QSC EX1600 amplifier. The schematic for it can be found here:


                I do not have the amplifier open yet. Right now this is a general question. I will send pics as I go.

                Comment

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